Roofs for contemporary buildings, particularly light industrial buildings having rectangular-shaped roofing, typically are formed from roof panel structures that are attached to main supporting beams. In general, a roof panel structure includes a purlin (i.e., a major beam) that, when installed, is attached orthogonally to the main supporting beams of the structure, subpurlins (i.e., minor beams such as lumber stiffeners) that are attached orthogonally to the purlin, and diaphragms (e.g., wood structural panels) that are nailed to the subpurlins and the purlin for structural and shear support. Completed roof panel structures may be 25 to 80 feet in length or even longer, and are often lifted to and placed on the main supporting beams by a crane or forklift. Once in place, the roof panel structures are typically nailed to the main supporting beams and adjacent roof panel structures.
In practice, each of the components of the roof panel structures is brought to a site and the roof panel structures are assembled by hand. Some manufacturers preassemble the subpurlins and the diaphragms offsite (typically in four-foot segments, but sometimes in eight-foot segments), and use the preassembled subpurlins and diaphragms at the site to form the roof panel structures. Even if the preassemblies are used, however, many carpenters and other construction workers are required in the roofing area to complete assembly and/or installation of the roof panel structures. Thus, although present roof panel structures work well for their intended purpose, their assembly can be time consuming and expensive. Moreover, the amount of labor involved may introduce errors into assembly, which may cause additional expenses of time, labor, and materials. In addition, the labor involved may be somewhat dangerous and/or strenuous, and very often requires young, attentive workers.